Anti-clogging device for barrel assembly of a downhole pump

ABSTRACT

An anti-clogging device for a barrel assembly of a downhole pump inserted in a well is provided. The anti-clogging device includes an upper shank portion having means for removably securing the anti-clogging device to a lower end of the barrel assembly, and a lower functional portion extending from a lower end of the upper shank portion,. The lower functional portion includes means for creating turbulence in a mixture of liquid, sand and dirt mixture in the well as the barrel assembly moves up and down. An outer surface of the upper shank portion of the anti-clogging device may be provided with male threads which threadabtly engage corresponding female threads in the lower end of the barrel assembly. A plurality of grooves are formed in an outer surface of the lower functional section at an angle relative to a vertical axis of the device. Also provided as part of the turbulence creating means is a plurality of teeth extending downwardly from a lower end of the lower functional portion of the anti-clogging device.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a device for improving the performanceof downhole pumps commonly used in the oil industry. More specifically,the present invention relates to a device at the end of the barrelassembly of a bottom hole pump for preventing the buildup of sand anddirt outside the pump between the tubing and the barrel.

Description of the Related Art

Beam pumping, or the sucker-rod lift method, is the oldest and mostwidely used type of artificial lift for most wells. A sucker-rod pumpingsystem is made up of several components, some of which operate aboveground and other parts of which operate underground, down in the well.As shown in FIG. 1, the surface-pumping unit 10, which drives theunderground pump, consists of a prime mover 12 (usually an electricmotor) and, normally, a beam 14, also known as a walking beam, fixed toa pivotal post 16, also known as a Sampson post. This system allows thebeam 14 to rock back and forth, moving the downhole components up anddown in the process. The entire surface system 10 is run by a primemover 12, V-belt drives 18, and a gearbox with a crank mechanism on it.When this type of system is used, it is usually called a beam-pumpinstallation. However, other types of surface-pumping units can be used,including hydraulically actuated units (with and without some type ofcounterbalancing system), or even tall-tower systems that use a chain orbelt to allow long strokes and slow pumping speeds. The more-genericname of sucker-rod lift, or sucker-rod pumping, should be used to referto all types of reciprocating rod-lift methods.

The underground pumping unit 20 includes a string of linked sucker rods22 attached to an underground pump 24. The linked sucker rods 22 and areusually long steel rods, from ⅝ to more than 1 or 1¼ in. in diameterthat are screwed together in 25- or 30-ft lengths. The string of linkedsucker rods 22 fit inside the tubing 23 and are stroked up and down bythe surface-pumping unit 10. This activates the downhole,positive-displacement pump 24 at the bottom of the well. Each time therods 22 and pumps 24 are stroked, a volume of produced fluid is liftedthrough the sucker-rod tubing annulus and discharged at the surface.

The pump 24, also known as a sucker rod pump, bottom hole pump,subsurface pump, or reciprocating pump, is used to pump fluid to the topof the ground. There are two types of sucker rod pumps, the tubing pumpstyle and the insert pump. Both styles of pump generally consist of abarrel assembly 25, a stationary valve 26 and a traveling valve 27attached to a plunger 28. The pump 24 is placed at a depth where it willbe covered by fluid while it is pumping. A holddown 29 may be utilizedin either style pump at the bottom of the well to hold the pump 24 inits working position.

By way of example, a traveling barrel bottom holddown insert pump 24 isshown in FIG. 2A and FIG. 2B. When using an insert pump, the completepump 24 is run in the well on the bottom of the linked sucker rods 22.The plunger 28 is stationary and attaches to the holddown 29 with ahollow pull tube 21. The stationary valve 26 is located at the top ofthe plunger 28, and the traveling valve 27 at the top of the barrelassembly 25, which is attached the the sucker rod string 22.

On the up stroke, shown in FIG. 2B, the barrel assembly 25 is pulled up,the traveling valve 27 closes, the stationary valve 26 opens, and fluidis lifted upward through the hollow pull tube 21 into the region betweenthe plunger 28 and the barrel assembly 25. On the down stroke, shown inFIG. 2A, when the pressure below the traveling valve 27 becomes greaterthan the pressure above it, it opens. As the barrel assembly 25 travelsdownward, the stationary valve 26 closes trapping the fluid above it andpushing it though the open traveling valve 27 upward into the tubing 23,and, eventually, to the surface.

Traveling barrel bottom holddown insert pumps such as the one shown inFIG. 2A and FIG. 2B, are recognized as being good for use in dirty,sandy wells because the movement of the barrel assembly 25 keeps thesand moving so it can't settle around the holddown 29. However, inpractice, in areas where sand and dirt are prevalent, the pumps stillfrequently get clogged which requires the retrieval of the pump from thedownhole for inspection and cleaning periodically.

Accordingly, there is a need for a device at the lower end of the barrelassembly of a downhole pump which better protects against the settlingof sand and dirt between the holddown and the end of the barrelassembly.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a devicewhich better protects against, reduces, and effectively prevents thesettling of sand and dirt between the holddown and the end of at thebarrel assembly of a downhole pump.

The present invention meets these objects by providing an anti-cloggingdevice for the barrel assembly of a downhole pump. The present inventionmeets these objectives by providing a device having a plurality ofangled grooves in the outer surface thereof. The device can be attachedto the end of the barrel assembly of a downhole pump and createsturbulence in the mixture of liquid, sand and dirt thereby preventing abuildup of sand and dirt in the area between the holddown and the barrelassembly.

According to one aspect of the present invention, there is provided ananti-clogging device for a barrel assembly of a downhole pump insertedin a well. The anti-clogging device includes an upper shank portionhaving means for removably securing the anti-clogging device to a lowerend of the barrel assembly, and a lower functional portion extendingfrom a lower end of the upper shank portion,. The lower functionalportion includes means for creating turbulence in a mixture of liquid,sand and dirt mixture in the well as the barrel assembly moves up anddown. An outer surface of the upper shank portion of the anti-cloggingdevice may be provided with male threads which threadabtly engagecorresponding female threads in the lower end of the barrel assembly.

The turbulence creating means according to one aspect of the inventioncomprises a plurality of grooves formed in an outer surface of the lowerfunctional section at an angle relative to a vertical axis of thedevice. Preferably, each groove is oriented at an angle of 40 degreesfrom the vertical axis, and nine angled grooves are provided.

The turbulence creating means according to a further aspect of theinvention comprises a plurality of teeth extending downwardly from alower end of the lower functional portion of the anti-clogging device.Preferably, the faces of the teeth are oriented at an angle of 15degrees relative to the horizontal axis of the lower end of the lowerfunctional portion of the anti-clogging device, and nine teeth areprovided. The nine teeth extend from the lower end of the lowerfunctional position of the anti-clogging device at locations betweeneach corresponding one of the nine grooves.

According to a further aspect of the invention, each groove has an openfirst end at the lower end of the lower functional portion of theanti-clogging device and a closed second end at a point near an upperend of the lower functional portion of the anti-clogging device. Theanti-clogging device is made from a strong, anti-corrosive material,such as, according to one aspect of the invention, 316 Stainless Steel.

Yet another aspect of the invention is an anti-clogging device for abarrel assembly of a downhole pump inserted in a well having a pluralityof grooves and teeth. The plurality of grooves may be formed in an outersurface of a lower region of the barrel assembly. Each groove is formedat an angle relative to a vertical axis of the device. The plurality ofteeth extend downwardly from a lower end of the lower region of thebarrel assembly. Preferably, each groove is oriented at an angle of 40degrees from the vertical axis, and the faces of the teeth are orientedat an angle of 15 degrees relative to the horizontal axis of the lowerend of the barrel assembly.

These and other objects, features and advantages of the presentinvention will become apparent from a review of the following drawingsand detailed description of the preferred embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can best be understood in connection with theaccompanying drawings. It is noted that the invention is not limited tothe precise embodiments shown in the drawings, in which:

FIG. 1 is a schematic view of downhole sucker rod pumping system as isknown in the prior art.

FIG. 2A is a schematic view of a traveling barrel bottom holddown insertpump as is known in the prior art with the pump shown in the downstroke.

FIG. 2B is a schematic view of a traveling barrel bottom holddown insertpump as is known in the prior art with the pump shown in the up stroke.

FIG. 3 is a side view in elevation of an anti-clogging device for thebarrel assembly of a downhole pump according to on presently preferredembodiment on the invention.

FIG. 4 is a top plan view of the anti-clogging device for the barrelassembly of a downhole pump shown in FIG. 3.

FIG. 5 is a bottom plan view of the anti-clogging device for the barrelassembly of a downhole pump shown in FIG. 3.

DETAILED DESCRIPTION OF THE INVENTION

For purposes of promoting and understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended. The invention includes any alterationsand further modifications in the illustrated devices and describedmethods and further applications of the principles of the invention thatwould normally occur to one skilled in the art to which the inventionrelates.

As best shown in FIG. 3-FIG. 5, one presently preferred embodiment ofthe invention comprises an anti-clogging device 40 for the barrelassembly 25 of a downhole pump 24. The anti-clogging device 40 has anupper shank portion 41 and a lower functional portion 42. Means areprovided for securing the anti-clogging device 40 to the lower end ofthe barrel assembly 25. According to the preferred embodiment, the outersurface of the shank portion 41 of the anti-clogging device 40 isprovided with male threads 43 which threadabtly engage correspondingfemale threads in the open lower end of the barrel assembly 25.

The outer surface of the lower functional portion 42 of theanti-clogging device 40 is provided with a plurality of grooves 44therein. The grooves are formed in the outer surface of the lowersection 42 at an angle relative to the vertical axis of the device 40.The angled grooves 44 create additional turbulence in the liquid, sand,dirt mixture in the well as the barrel assembly 25 moves up and down inthe tube 23. According to one preferred embodiment, nine (9) angledgrooves 44 are provided in the outer surface of the lower section 42with each groove oriented at an angle of 40 degrees from the verticalaxis.

A plurality of teeth 45 are also provided at the lower edge of the lowersection 42 to further promote turbulence in the liquid, sand, dirtmixture in the well. The teeth 45 also help to dislodge any sand anddirt that may have settled atop the holddown 29 when the traveling valve27 and barrel assembly 25 are at the end of the downstroke. According toa preferred embodiment, nine (9) teeth 45 corresponding to the nine (9)grooves 44 are provided, and the face of the teeth 45 are oriented at anangle of 15 degrees relative to the horizontal axis of the lower portion42 of the anti-clog device 40.

Because of the moisture and harsh environment that the anti-clog device40 may be exposed to, it is necessary that the device be made from astrong, anti-corrosive material. According to one presently preferredembodiment, the anti-clog device 40 is formed from 316 Stainless Steel.

It is also anticipated that means other than male threads 43 may beimplemented for connecting the anti-clog device 40 to the barrelassembly 25. Further, it is understood and within the scope of theinvention to form the grooves 44 and teeth 45 directly in the outersurface at the end region of the barrel assembly 25, thus avoiding theneed for a separate connected device.

This detailed description, and particularly the specific details of theexemplary embodiment disclosed, is given primarily for clearness ofunderstanding and no unnecessary limitations are to be understoodtherefrom, for modifications will become evident to those skilled in theart upon reading this disclosure and may be made without departing fromthe spirit or scope of the claimed invention.

I claim:
 1. An anti-clogging device for a barrel assembly of a downholepump inserted in a well comprising: an upper shank portion having meansfor removably securing the anti-clogging device to a lower end of thebarrel assembly; a lower functional portion extending from a lower endof the upper shank portion, said lower functional portion includingmeans for creating turbulence in a mixture of liquid, sand and dirtmixture in the well as the barrel assembly moves up and down.
 2. Theanti-clogging device according to claim 1, wherein an outer surface ofthe upper shank portion of the anti-clogging device is provided withmale threads which threadabtly engage corresponding female threads inthe lower end of the barrel assembly.
 3. The anti-clogging deviceaccording to claim 1, wherein the turbulence creating means comprises aplurality of grooves formed in an outer surface of the lower sectionfunctional section at an angle relative to a vertical axis of thedevice.
 4. The anti-clogging device according to claim 3, wherein eachgroove is oriented at an angle of 40 degrees from the vertical axis. 5.The anti-clogging device according to claim 3, wherein nine angledgrooves are provided in the outer surface of the lower functionalsection.
 6. The anti-clogging device according to claim 5, wherein eachgroove is oriented at an angle of 40 degrees from the vertical axis. 7.The anti-clogging device according to claim 6, wherein the turbulencecreating means further comprises a plurality of teeth extendingdownwardly from a lower end of the lower functional portion of theanti-clogging device.
 8. The anti-clogging device according to claim 7,wherein faces of the teeth are oriented at an angle of 15 degreesrelative to the horizontal axis of the lower end of the lower functionalportion of the anti-clogging device.
 9. The anti-clogging deviceaccording to claim 8, wherein nine teeth are provided, said nine teethextending from the lower end of the lower functional position of theanti-clogging device at locations between each corresponding one of thenine grooves.
 10. The anti-clogging device according to claim 3, whereinthe turbulence creating means further comprises a plurality of teethextending downwardly from a lower end of the lower functional portion ofthe anti-clogging device.
 11. The anti-clogging device according toclaim 10, wherein faces of the teeth are oriented at an angle of 15degrees relative to the horizontal axis of the lower end of the lowerfunctional portion of the anti-clogging device.
 12. The anti-cloggingdevice according to claim 1, wherein the turbulence creating meansfurther comprises a plurality of teeth extending downwardly from a lowerend of the lower functional portion of the anti-clogging device.
 13. Theanti-clogging device according to claim 12, wherein faces of the teethare oriented at an angle of 15 degrees relative to the horizontal axisof the lower end of the lower functional portion of the anti-cloggingdevice.
 14. The anti-clogging device according to claim 3 wherein eachgroove has an open first end at the lower end of the lower functionalportion of the anti-clogging device and a closed second end at a pointnear an upper end of the lower functional portion of the anti-cloggingdevice.
 15. The anti-clogging device according to claim 1 wherein theanti-clogging device is made from a strong, anti-corrosive material. 16.The anti-clogging device according to claim 15, wherein the anti-clogdevice is formed from 316 Stainless Steel.
 17. An anti-clogging devicefor a barrel assembly of a downhole pump inserted in a well comprising:a plurality of grooves formed in an outer surface of a lower region ofthe barrel assembly, each of said grooves formed at an angle relative toa vertical axis of the device; and a plurality of teeth extendingdownwardly from a lower end of the lower region of the barrel assembly.18. The anti-clogging device according to claim 17, wherein each grooveis oriented at an angle of 40 degrees from the vertical axis.
 19. Theanti-clogging device according to claim 18, wherein faces of the teethare oriented at an angle of 15 degrees relative to the horizontal axisof the lower end of the barrel assembly.